412
FXAK68 PAFC 271343
AFDAFC
SOUTHCENTRAL AND SOUTHWEST ALASKA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE ANCHORAGE AK
543 AM AKDT TUE OCT 27 2026
.SHORT TERM FORECAST SOUTHCENTRAL ALASKA (DAYS 1 THROUGH
3/TODAY THROUGH THURSDAY NIGHT)...
A HIGH AMPLITUDE RIDGE IS BUILDING OVER SOUTHCENTRAL TODAY
BRINGING WARMER TEMPERATURES ALOFT AND A STOUT INVERSION.
THIS IS A SETUP RIPE FOR FOG DEVELOPMENT, AND ALONG COOK INLET,
IT IS NOT DISAPPOINTING THIS MORNING AS FOG HAS DEVELOPED IN
NUMEROUS LOCATIONS. IT IS DIFFICULT TO GET A GOOD VIEW FROM
SATELLITE IMAGERY OF THE EXTENT OF THE FOG DUE TO CIRRUS
EXTENDING OVER THE SUSITNA VALLEY THROUGH THE KENAI PENINSULA DUE
TO A WEAK SHORTWAVE AHEAD OF THIS RIDGE. HOWEVER, FROM
OBSERVATIONS AND SOME WEBCAMS, IT CAN BE SEEN IN ANCHORAGE,
PORTAGE, AND TALKEETNA. IN ANCHORAGE EARLY THIS MORNING, THE FOG
IS MOSTLY RELEGATED TO AREAS WITHIN A MILE OF THE INLET, SO IT IS
OCCURRING IN WEST ANCHORAGE TO DOWNTOWN WITH OTHER AREAS OF THE
ANCHORAGE BOWL WITHOUT ANY FOG. WHILE THE FOG IS EXPECTED TO
DISSIPATE AS THE DAY PROGRESSES, AREAS OF FOG ARE LIKELY AGAIN
TONIGHT INTO WEDNESDAY. FOR AREAS NOT EXPERIENCING FOG, IT SHOULD
BE A NICE, SUNNY DAY BOTH TODAY AND WEDNESDAY.
THE NEXT SIGNIFICANT CHANGE IN WEATHER WILL COME WEDNESDAY NIGHT
INTO THURSDAY AS THE RIDGE IS PUSHED EASTWARD BY A SHORT-WAVE
TROUGH AND SURFACE FRONTAL SYSTEM ARRIVING FROM THE BERING SEA.
MOST OF THE IMPACTS WILL BE FROM KODIAK TO THE KENAI PENINSULA,
ANCHORAGE, AND MAT-SU. THE FRONT WILL BE OCCLUDING AS IT
APPROACHES SOUTHCENTRAL AND THERE WON'T BE MUCH IN THE WAY OF WARM
AIR ADVECTION. STILL, THIS WILL BE PRIMARILY A RAIN EVENT FOR
LOWER ELEVATIONS FROM THE MAT VALLEY TO ANCHORAGE AND THE KENAI
PENINSULA. THE SUSITNA VALLEY IS THE ONE PLACE THAT WILL LIKELY
SEE SOME LIGHT SNOW ACCUMULATION. THE TROUGH AND THE FRONT WILL
QUICKLY WEAKEN AS THEY PROGRESS EASTWARD, WITH ANOTHER STRONG
STORM SYSTEM TRACKING INTO THE BERING AND CAUSING A NEW RIDGE TO
BUILD AND OVERTAKE THE SHORT-WAVE OVER SOUTHCENTRAL. THUS, DRY
CONDITIONS WILL HOLD IN LONGER FOR CORDOVA, VALDEZ, AND THE COPPER
RIVER BASIN.
STRONGER AND MORE PROGRESSIVE FLOW ALOFT WITH THIS NEXT BERING
SYSTEM WILL BRING WILL BRING A LEADING FRONTAL SYSTEM BARRELING
INTO THE WESTERN GULF AND SOUTHCENTRAL BY LATE THURSDAY. THERE IS
HIGH CONFIDENCE (75-90%) THAT THIS SYSTEM WILL BRING WIDESPREAD
HEAVY RAIN AND WIND TO KODIAK, THE GULF COASTAL WATERS, AND MUCH
OF SOUTHCENTRAL ALASKA AS WE CONTINUE THROUGH THE REMAINDER OF THE
WORK WEEK.
-EZ/SEB
.SHORT TERM FORECAST SOUTHWEST ALASKA/BERING SEA/ALEUTIANS (DAYS
1 THROUGH 3)...
KEY MESSAGES:
* PROLONGED SOUTHERLY / SOUTHWESTERLY WINDS MAKE CONDITIONS
FAVORABLE FOR MINOR-MODERATE FLOODING ALONG THE KUSKOKWIM DELTA.
A FRONT IS CURRENTLY MOVING THROUGH THE BERING AND IS BRINGING A
LINE OF RAINFALL AND GUSTY WINDS IN A LINE THROUGH THE PRIBILOF
ISLANDS AND THE ADAK AND ATKA AREA. STRONG RIDGING IS PRESENT OVER
MUCH OF MAINLAND ALASKA, LEADING TO LIGHTER WINDS AND CLEARER
SKIES. THERE IS SOME FOG AND LOW STRATUS FORMING ALONG THE
COASTLINE OF THE SOUTHWEST MAINLAND FROM THE ALASKA PENINSULA TO
THE KUSKOKWIM DELTA COAST. THE FRONT WILL INITIALLY STALL ON THE
RIDGE, UNABLE TO BYPASS IT, SO LESS ACTIVE WEATHER PREVAILS OVER
THE SOUTHWEST MAINLAND THROUGH WEDNESDAY MORNING. AN EXCEPTION IS
THE KUSKOKWIM DELTA, WHICH WILL SEE CONTINUED GUSTY SOUTH TO
SOUTHWESTERLY WINDS. DUE TO THIS CONSISTENT FLOW AND HIGHER TIDES,
ELEVATED WATER LEVELS IS EXPECTED ALONG THE KUSKOKWIM COAST. DUE
TO THE WINDS AND WATER LEVELS, A WIND ADVISORY AND A HIGH SURF
ADVISORY REMAIN IN EFFECT THROUGH WEDNESDAY FOR THE KUSKOKWIM
DELTA. A SHORTWAVE PUSHES INTO THE BERING WEDNESDAY MORNING AND
ALLOWS THE FRONT TO OVERCOME THE RIDGE AND PUSH INTO SOUTHWEST
ALASKA. A SWATH OF RAINFALL WILL MOVE INLAND AS A RESULT.
A LARGE LOW ASSOCIATED WITH THE REMNANTS OF EX-TYPHOON CHAMPI MOVES
INTO THE BERING ON THURSDAY. THIS LOW BRINGS STORM FORCE AND GALE
FORCE WINDS TO THE ALEUTIANS, AS WELL AS CONTINUED SOUTH TO
SOUTHWEST FLOW TO THE KUSKOKWIM DELTA THURSDAY AND FRIDAY. HIGH
TIDES STEADILY RISE THROUGH FRIDAY, SO HIGHER WATER LEVELS ARE
MORE LIKELY FOR THE KUSKOKWIM DELTA COAST. WIDESPREAD
PRECIPITATION IS ALSO EXPECTED WITH THE LOW'S ARRIVAL IN THE
BERING, WITH THE LOW'S FRONT BRINGING STEADY RAINFALL TO THE
SOUTHWEST MAINLAND AS WELL.
-JAR
LONG TERM FORECAST (DAYS 4 THROUGH 7: FRIDAY THROUGH MONDAY)
THE LONG TERM LOOKS TO REMAIN QUITE ACTIVE, PARTICULARLY FOR THE
BERING SEA, ALEUTIAN CHAIN, AND SOUTHWEST ALASKA LOCATIONS. BY
FRIDAY, THE GLOBAL MODELS ARE IN FAIRLY GOOD AGREEMENT AND DEPICT
EX-TYPHOON CHAMPI AS A LARGE, DEEP, AND OCCLUDED LOW PRESSURE
SYSTEM MOVING EASTWARD ACROSS THE BERING WITH ITS FRONT QUICKLY
ENTERING THE GULF OF ALASKA. AS THE FRONT NEARS THE GULF COAST,
EXPECT COASTAL RIDGING AND A RETURN OF GAP WINDS FOR SOUTHCENTRAL
FOR THE TURNAGAIN ARM, KNIK RIVER VALLEY, AND COPPER RIVER BASIN.
FOR THE WEST, THE BIGGEST HAZARD WITH THIS SYSTEM WILL BE WIND,
AND THE GFS HAS STORM FORCE WINDS IN THE BOUNDARY LAYER FRIDAY
AFTERNOON MOVING ACROSS THE SOUTHERN BERING AND CENTRAL ALEUTIANS
ON THE BACKSIDE OF THE SYSTEM. THE SURFACE LOW WILL BE WEAKENING
AS IT MOVES INLAND INTO SOUTHWEST ALASKA, WITH STRONG
NORTHWESTERLY GAP WINDS BECOMING A COMMON THEME FOR THE CENTRAL
AND EASTERN ALEUTIANS BY SATURDAY MORNING. PATTERN RECOGNITION
SUGGESTS THAT ONE PLACE TO WATCH WILL BE COLD BAY, AS NORTHWEST
WINDS CAN BE ESPECIALLY ENHANCED THROUGH THE GAP THERE. EXPECT GAP
WINDS ELSEWHERE TO BE ELEVATED, BUT GENERALLY DECREASING IN
INTENSITY THROUGH THE FAVORED BAYS AND PASSES OF THE ALASKA
PENINSULA THROUGH SATURDAY AFTERNOON. MODELS ALSO SHOW (TO SOME
DEGREE) A SECONDARY LOW PRESSURE SYSTEM SITUATED OFF THE KAMCHATKA
PENINSULA FOR THE WEEKEND. STILL QUITE A BIT OF SPREAD ON THIS
SYSTEM AS THE GFS REMAINS THE MUCH MORE BULLISH/STRONGER SOLUTION
WHILE OTHER MODEL GUIDANCE CONTINUES TO STRUGGLE RESOLVING THIS
SYSTEM IN TERMS OF INTENSITY AND POSITIONING. 850 MB TEMPERATURE
ANOMALIES SUGGEST THAT TEMPERATURES STAY AT OR ABOVE AVERAGE
THROUGH THE END OF THE LONG TERM FOR THE BOTH THE WEST AND EAST.
-AM
AVIATION
PANC...MOSTLY VFR CONDITIONS AND LIGHT WINDS WILL PERSIST. FOG IS
EXPECTED THROUGH THIS MORNING, BRINGING CONDITIONS DOWN TO IFR-
LIFR. FOG IS EXPECTED TO LIFT LATER THIS MORNING. SCATTERED LOW
CLOUDS WILL PERSIST THROUGH TODAY.
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page